The efficiency is slightly low: The general charger inside also has the transformer, but the wireless charge to transmit the coil and the receiving coil composition transformer because in the structure limited, the energy transmission efficiency theoretically will be slightly lower than the general charger.

Charging speed is slow: due to the current mobile phone and other receiving devices, most of the limit of the input power, so the charging speed is slow.

High cost: In the charger need to drive the coil of the electronic circuit, and in the electrical device need to have a power conversion of electronic devices, both need a wire loop, and need high-frequency filter circuit to meet electromagnetic compatibility, so the cost is higher than the direct charge.